Protection of seeds against birds



Patented Jan. 18, 1944 UNITED STATES PATENT OFFICE PROTECTION OF SEEDS AGAINST BIRDS Franz Heckmanns, Leverkusen-Wiesdori', and

Marianne Meisenheimer, Leverkusen-Kuppersteg, Germany, assignors to Winthrop Chemical Company, Inc., New York, N. Y., a corporation of New York No Drawing. Application July 29, 1941, Serial No. 404,524. In Germany June 19, 1940 6 Claims.

this purpose dyestuffs, such as Prussian-blue or red-iron oxides as well as carbon-black, have been used to color the grain. Tarry products and tarsoaps which contain ill-tasting and ill-smelling substances, such as pyridine, were employed to keep the crows away from the seeds. By the simultaneous application of severalsubstances, each displaying a different action, it was sought to increase the efiicacy of such treatment. In

most cases, however, these experiments had no.

practical success sincethepreparations caused injuries to the seeds, they were not efficacious enough or their price was prohibitive. Only liquid tarry. products have been recognized by the art and are to be found on the market. Their use necessitates, however, a cumbersome treatment and subsequent drying of the seed grain. It is tobe regarded as a special disadvantage of these preparations that in many cases they cause delay in the germination of the seeds. Solid mixtures of tar or liquid tarr-y products with solid fillers did not prove suitable for the purpose in question.

Now we have found that by a treatment with an anthraquinone or benzanthrone seeds are made unattractive to birds. The term an anthraquinone" whenever used in the description or the claims comprises not only anthraquinone of the formula but also dithioanthraquinone as well as their substitution products. The said anthraquinones may for instance bear alkyl, aryl, amino or sulfonic acid or carboxylic acid groups as well as halogen atoms as substituents of the nuclei. Suitable anthraquinones are for instance chlorinated or brominated anthraquinones, anthraquinone sulfonic acids" or their salts and aminoanthraquinones.

contain one or more substituents. As a rule anthraquinone (l) and its derivatives are more effective than dithioanthraquinone (2) and its derivatives. Furthermore, water-insoluble compounds of these series have proved to be more efficacious than water-soluble substances.

If the pure substances are employed they are preferably applied to the seed grain in conjunction with a solid filler or a liquid solvent. Generally preparations containing about 25% of the said compounds are eificacious in concentrations of 2-4zl000. The said substances may be admixed with solid inert filler such as talc, chalk, diatomaceous earth, pulverized brown-coal, slate flour, wood flour, gypsum, kieselguhr, bleaching earths, sodium carbonate or sodium bicarbonate.

The seed grain is then treated with these powders in the usual manner, The filler or diluent, too, may also exert a frightening action on the birds; red or black-iron oxide, iron hydroxide or carbon black may thus be used wholly or partially as a filler. The said compounds may also be applied to the seed grains in a liquid medium by spraying the seeds with such preparations or dipping the seeds therein. As liquid diluent water is especially suited. Such aqueous solutions may contain a wetting 0r dispersing agent. The seed grain may, however, also be treated with solutions of the said compounds in.

suitable organic solvents or oils.

The use of an inert solid filler is in general not necessary if instead of the pure compounds growth of plants such as phytohormones, for instance fi-indolylacetic, their homologues, for in- The anthraquinone may stance p-indolylpropionic acid or p-indolyl butyric acid or salts or esters of these acids may simultaneously be added.

It is understood that mixtures of two or more anthraquinones may be used for the purpose of' the invention.

Quinones, quinonimides or phenanthrenequi none have already been suggested as seed dressing agents. Nothing is, however, known about the possibility that these compounds may render seeds unattractive to birds.

The following examples illustrate the invention without, however, restricting it thereto:

Example 1 100 grs. of wheat were treated with a mixture of 25% anthraquinone and 75% talc and another portion of 100 grs. of wheat was treated with talc only. In both cases the proportion was 2:1000. The grains were set before crows in 2 shallow trays. The next day all the grains treated with talc had been eaten whereas 97.5 g. of uneaten grains treated with anthraquinone could be collected. All-the seed grains had absolutely the same appearance.

Example 2 Wheat was dusted with the substances or mixtures mentioned in the following table. Then it was buried in the soil. The place where the treated and (for control purposes) the untreated seeds had been sown-was surrounded by a cage. After having germinated the seeds were placed in a position freely accessible to crows. The untreated seeds were generally eaten, whereas the treated seeds were not devoured in several experiments.

The following quantities were efiective:

l-aminoanthraquinone 4: 1000 1,8-dich1oro-anthraquinone 4:1000 l-chloro-anthraquinone 4:1000' l-chloro-anthraquinone 2: 1000 Benzanthrone 4 1000 Benzanthrone Anthraquinone 2:1000 Anthraquinone, :50% talcum 2:1000 Anthraquinone, 25% talcum 2:1000 Residue obtained in the preparation of anthraquinone 4 10 00 Residue obtained in the preparation of calcium anthraquinone 1,&- disulphonate 4:1000 Residue obtained in preparation of dithioanthraquinone 8-10z1000 5. A process for protecting seeds against birds, which comprises applying benzanthrone to such seeds.

6. A process for protecting seeds against birds, which comprises applying to such seeds a quinone selected from the group consisting of anthraquinones and benzanthrone.

ERAN Z HECKMANNS. MARIANNE MEISENHEIMER. 

